Re: [PATCH v2] drm/msm/dpu: add display port support in DPU

[Jeykumar Sankaran <jsanka-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>]

On 2018-12-03 06:47, Sean Paul wrote:
> On Tue, Nov 27, 2018 at 02:28:30PM -0800, Jeykumar Sankaran wrote:
>> Add display port support in DPU by creating hooks
>> for DP encoder enumeration and encoder mode
>> initialization.
>> 
>> This change is based on the SDM845 Display port
>> driver changes[1].
>> 
>> changes in v2:
>> 	- rebase on [2] (Sean Paul)
>> 	- remove unwanted error checks and
>> 	  switch cases (Jordan Crouse)
>> 
>> [1] https://lwn.net/Articles/768265/
>> [2] https://lkml.org/lkml/2018/11/17/87
>> 
>> Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
>> ---
>>  drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c |  8 ++---
>>  drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c     | 47
> +++++++++++++++++++++++++----
>>  2 files changed, 45 insertions(+), 10 deletions(-)
>> 
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>> index d3f4501..1f6b4b1 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>> @@ -2015,7 +2015,7 @@ static int dpu_encoder_setup_display(struct
> dpu_encoder_virt *dpu_enc,
>>  {
>>  	int ret = 0;
>>  	int i = 0;
>> -	enum dpu_intf_type intf_type;
>> +	enum dpu_intf_type intf_type = INTF_NONE;
> 
> dpu_intf_type seems unnecessary, you could just use the 
> DRM_MODE_ENCODER_*
> value
> directly?
> 
>>  	struct dpu_enc_phys_init_params phys_params;
>> 
>>  	if (!dpu_enc || !dpu_kms) {
>> @@ -2038,9 +2038,9 @@ static int dpu_encoder_setup_display(struct
> dpu_encoder_virt *dpu_enc,
>>  	case DRM_MODE_ENCODER_DSI:
>>  		intf_type = INTF_DSI;
>>  		break;
>> -	default:
>> -		DPU_ERROR_ENC(dpu_enc, "unsupported display interface
> type\n");
>> -		return -EINVAL;
>> +	case DRM_MODE_ENCODER_TMDS:
>> +		intf_type = INTF_DP;
>> +		break;
>>  	}
>> 
>>  	WARN_ON(disp_info->num_of_h_tiles < 1);
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
>> index 985c855..7d931ae 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
>> @@ -473,6 +473,32 @@ static void _dpu_kms_initialize_dsi(struct
> drm_device *dev,
>>  	}
>>  }
>> 
>> +static void _dpu_kms_initialize_displayport(struct drm_device *dev,
>> +					    struct msm_drm_private *priv,
>> +					    struct dpu_kms *dpu_kms)
>> +{
>> +	struct drm_encoder *encoder = NULL;
>> +	int rc;
>> +
>> +	if (!priv->dp)
>> +		return;
>> +
>> +	encoder = dpu_encoder_init(dev, DRM_MODE_ENCODER_TMDS);
>> +	if (IS_ERR(encoder)) {
>> +		DPU_ERROR("encoder init failed for dsi display\n");
>> +		return;
>> +	}
>> +
>> +	rc = msm_dp_modeset_init(priv->dp, dev, encoder);
>> +	if (rc) {
>> +		DPU_ERROR("modeset_init failed for DP, rc = %d\n", rc);
>> +		drm_encoder_cleanup(encoder);
>> +		return;
>> +	}
>> +
>> +	priv->encoders[priv->num_encoders++] = encoder;
> 
> No need to keep track of drm resources at the driver level, the core 
> will
> do
> this for you. So can you please add a patch preceding this one to 
> remove
> the
> priv->encoders/crtc/planes/connectors arrays?
> 
priv arrays for tracking drm components and priv->num_** counters are 
introduced
by mdp4/5. DPU just adapted the implementation.

De-coupling DPU from these arrays is much easier than fixing them in 
mdp4/5. I see
mdp5 is using it to track the max resources and also in ./msm_fbdev.c.

Thanks and Regards,
Jeykumar S.
>> +}
>> +
>>  /**
>>   * _dpu_kms_setup_displays - create encoders, bridges and connectors
>>   *                           for underlying displays
>> @@ -487,6 +513,8 @@ static void _dpu_kms_setup_displays(struct
> drm_device *dev,
> 
> Why are these functions voids? Seems like there are plenty of places 
> for
> them to
> fail :)
> 
> Let's add a patch to the beginning of this series to properly handle
> failures in
> setup_displays and initialize_dsi
> 
>>  {
>>  	_dpu_kms_initialize_dsi(dev, priv, dpu_kms);
>> 
>> +	_dpu_kms_initialize_displayport(dev, priv, dpu_kms);
>> +
>>  	/**
>>  	 * Extend this function to initialize other
>>  	 * types of displays
>> @@ -723,13 +751,20 @@ static void _dpu_kms_set_encoder_mode(struct
> msm_kms *kms,
>>  	info.capabilities = cmd_mode ? MSM_DISPLAY_CAP_CMD_MODE :
>>  			MSM_DISPLAY_CAP_VID_MODE;
>> 
>> -	/* TODO: No support for DSI swap */
>> -	for (i = 0; i < ARRAY_SIZE(priv->dsi); i++) {
>> -		if (priv->dsi[i]) {
>> -			info.h_tile_instance[info.num_of_h_tiles] = i;
>> -			info.num_of_h_tiles++;
>> +	switch (info.intf_type) {
>> +	case DRM_MODE_ENCODER_DSI:
>> +		/* TODO: No support for DSI swap */
>> +		for (i = 0; i < ARRAY_SIZE(priv->dsi); i++) {
>> +			if (priv->dsi[i]) {
>> +				info.h_tile_instance[info.num_of_h_tiles]
> = i;
>> +				info.num_of_h_tiles++;
>> +			}
>>  		}
>> -	}
>> +		break;
>> +	case DRM_MODE_ENCODER_TMDS:
>> +		info.num_of_h_tiles = 1;
>> +		break;
>> +	};
>> 
>>  	rc = dpu_encoder_setup(encoder->dev, encoder, &info);
>>  	if (rc)
>> --
>> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
> Forum,
>> a Linux Foundation Collaborative Project
>> 
>> _______________________________________________
>> Freedreno mailing list
>> Freedreno@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/freedreno

-- 
Jeykumar S
_______________________________________________
Freedreno mailing list
Freedreno@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/freedreno